is worth buying it now that it's showing up at discount. And it's worth playing it to get 92% or more completion to get the "Good Ending".

What is definitely NOT worth it is to go for 100% completion just to see the "Perfect Ending"!
92% seems too much, I'm only at 18% at chapter 2 and I dont think I can even go past 40 because they all go up by 1 and It's hard to find new ones. Should i just go along with it? does the ending matter that much?.